ELECTRIC DRIVE MODULE HAVING MOTOR WITH HEAT SINK INSERT IN ROTOR SHAFT

A motor drive system has a rotor assembly that is rotatable about an axis and includes a hollow shaft, a tube, and one or more fin sets. The tube is received in the shaft and defines a first passage. The fin sets are disposed about the tube and are engaged to the shaft. Each fin set defines a plurality of circumferentially spaced apart fins that are coupled to the shaft and the tube. The first passage is configured to discharge fluid communicated therethrough into a return chamber that is formed in the rotor assembly. A plurality of second passages are formed between the shaft and fins and are in fluid communication with the return chamber.